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Diffstat (limited to 'security/device_cgroup.c')
-rw-r--r--security/device_cgroup.c38
1 files changed, 28 insertions, 10 deletions
diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 4ea583689ee..fd764a0858d 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -49,10 +49,14 @@ struct dev_cgroup {
spinlock_t lock;
};
+static inline struct dev_cgroup *css_to_devcgroup(struct cgroup_subsys_state *s)
+{
+ return container_of(s, struct dev_cgroup, css);
+}
+
static inline struct dev_cgroup *cgroup_to_devcgroup(struct cgroup *cgroup)
{
- return container_of(cgroup_subsys_state(cgroup, devices_subsys_id),
- struct dev_cgroup, css);
+ return css_to_devcgroup(cgroup_subsys_state(cgroup, devices_subsys_id));
}
struct cgroup_subsys devices_subsys;
@@ -102,7 +106,7 @@ free_and_exit:
static int dev_whitelist_add(struct dev_cgroup *dev_cgroup,
struct dev_whitelist_item *wh)
{
- struct dev_whitelist_item *whcopy;
+ struct dev_whitelist_item *whcopy, *walk;
whcopy = kmalloc(sizeof(*whcopy), GFP_KERNEL);
if (!whcopy)
@@ -110,7 +114,21 @@ static int dev_whitelist_add(struct dev_cgroup *dev_cgroup,
memcpy(whcopy, wh, sizeof(*whcopy));
spin_lock(&dev_cgroup->lock);
- list_add_tail(&whcopy->list, &dev_cgroup->whitelist);
+ list_for_each_entry(walk, &dev_cgroup->whitelist, list) {
+ if (walk->type != wh->type)
+ continue;
+ if (walk->major != wh->major)
+ continue;
+ if (walk->minor != wh->minor)
+ continue;
+
+ walk->access |= wh->access;
+ kfree(whcopy);
+ whcopy = NULL;
+ }
+
+ if (whcopy != NULL)
+ list_add_tail(&whcopy->list, &dev_cgroup->whitelist);
spin_unlock(&dev_cgroup->lock);
return 0;
}
@@ -364,6 +382,8 @@ static ssize_t devcgroup_access_write(struct cgroup *cgroup, struct cftype *cft,
case 'a':
wh.type = DEV_ALL;
wh.access = ACC_MASK;
+ wh.major = ~0;
+ wh.minor = ~0;
goto handle;
case 'b':
wh.type = DEV_BLOCK;
@@ -502,7 +522,6 @@ struct cgroup_subsys devices_subsys = {
int devcgroup_inode_permission(struct inode *inode, int mask)
{
- struct cgroup *cgroup;
struct dev_cgroup *dev_cgroup;
struct dev_whitelist_item *wh;
@@ -511,8 +530,8 @@ int devcgroup_inode_permission(struct inode *inode, int mask)
return 0;
if (!S_ISBLK(inode->i_mode) && !S_ISCHR(inode->i_mode))
return 0;
- cgroup = task_cgroup(current, devices_subsys.subsys_id);
- dev_cgroup = cgroup_to_devcgroup(cgroup);
+ dev_cgroup = css_to_devcgroup(task_subsys_state(current,
+ devices_subsys_id));
if (!dev_cgroup)
return 0;
@@ -543,12 +562,11 @@ acc_check:
int devcgroup_inode_mknod(int mode, dev_t dev)
{
- struct cgroup *cgroup;
struct dev_cgroup *dev_cgroup;
struct dev_whitelist_item *wh;
- cgroup = task_cgroup(current, devices_subsys.subsys_id);
- dev_cgroup = cgroup_to_devcgroup(cgroup);
+ dev_cgroup = css_to_devcgroup(task_subsys_state(current,
+ devices_subsys_id));
if (!dev_cgroup)
return 0;